1. Field of the Invention
This invention relates to the wiper device to wipe, for example, automobile windshields, particularly to the raindrop detection wiper which operates automatically by detecting raindrops.
2. Description of the Prior Art
FIG. 3 shows an example of the conventional wiper.
An intermittence control circuit (101) is connected to a drive circuit (102) in a wiper device (100) shown in the diagram.
A wiper motor (103) connects to the drive circuit (102), and an output shaft (103a) of the wiper motor (103) connects to a wiper arm (106) fitted with a wiper blade (105) through a link joint (104).
The wiper motor (103) contains an automatic stop mechanism (103b) to stop the wiper blade (105) in the stop position (B) on a wiping surface (110). The automatic stop mechanism (103b) is provided with an outer conducting plate (103c) and an inner conducting plate (103d), interlocking to the output shaft (103a).
The automatic stop mechanism (103b) is provided with a contact (103e), which connects with and disconnects from the outer conducting plate (103c), on one side and a contact (103f), which connects with and disconnects from the inner conducting plate (103d), on the other side.
Power is supplied to the wiper motor (103) through the drive circuit (102) to operate the wiper motor (103).
The output shaft (103a) rotates when the wiper motor (103) operates, and the wiper arm (106) swings reciprocatingly through the link joint (104) so that the wiper blade (105) wipes the wiping surface (110) between the stop position (B) and turn back position (A).
The wiper motor (103) is operated in accordance with the set time of the timer, which is not illustrated, installed in the intermittence control circuit (101). The wiper motor (103) is stopped by the function of the automatic stop mechanism (103b) at the state in which the wiper blade (105) is stopped at the stop position (B).
However, above-mentioned conventional wiper device (100) operates the wiper motor (103) in accordance with the instructions given by the intermittence control circuit (101). Therefore, in the case of actuating the wiper blade (105), the switch has to be selected by manual operation, causing extra trouble. A solution of this problem has been a challenge.